Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 21

Search results for: Lemhaba Ould Yarba

21 Trophic Ecology of Sarotherodon Melanotheron Heudelotii and Tilapia Guineensis from the Banc D'Arguin National Park, Mauritania

Authors: Néné Gallé Kide, Mamadou Dia, Lemhaba Ould Yarba, Youssouf Kone, Fatimetou Mint Khalil, Hajar Bouksir, Ghislane Salhi, Younès Saoud

Abstract:

The diet of Sarotherodon melanotheron and Tilapia guineensis were investigated in the National Park of Banc d'Arguin (PNBA) from September 2012 to October 2013. A total of 499 individuals ranging in size between 219 and 400 mm total length of S. melanotheron (253 males and 246 females), and 280 individuals of T.guineensis (229 males and 51 females) ranged between 180 and 424mm total length. We used for studying the feeding habits of both two species the frequency of occurrence method. The coefficient of emptiness was 40.88% for S. melanotheron and 38.57% for T. guineensis. Both two species were herbivorous and very close feedings. Their diet consists of Seagrass, green, red, blue, and brown algae, diatoms, gastropods, bivalves, Crustaceans, and mud. The Seagrass and green algae were prey preference of these two species. The diet feeding showed that the composition varies slightly depending on the season and size of individuals.

Keywords: national park, Cichlidae, trophic ecology, Banc d'Arguin, Mauritania

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20 Modeling of Silicon Window Layers for Solar Cells Based SIGE

Authors: B. Dennai, Meriem Boukais, A. Ould- Abbas

Abstract:

The efficiency of SiGe solar cells might be improved by a wide-band-gap window layer. In this work we were simulated using the one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D). In the modeling, the thickness of silicon window was varied from 80 to 150 nm. The rest of layer’s thicknesses were kept constant, by varying thickness of window layer the simulated device performance was demonstrate in the form of current-voltage (I-V) characteristics and quantum efficiency (QE).

Keywords: Modeling, Efficiency, conversion, SiGe, AMPS-1D, quantum efficiency

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19 Simulation Of Silicon Window Layers For Solar Cells Based Sige

Authors: A. Ould-Abbas, Boukais Meriem, B. Dennai

Abstract:

The efficiency of SiGe solar cells might be improved by a wide-band-gap window layer. In this work we were simulated using the one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D). In the simulation, the thickness of silicon window was varied from 80 to 150 nm. The rest of layer’s thicknesses were kept constant, by varying thickness of window layer the simulated device performance was demonstrate in the form of current-voltage (I-V) characteristics and quantum efficiency (QE).

Keywords: Simulation, Efficiency, conversion, SiGe, AMPS-1D, quantum efficiency

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18 Implementation and Validation of a Damage-Friction Constitutive Model for Concrete

Authors: M. Ould Ouali, N. E. Hannachi, L. Madouni

Abstract:

Two constitutive models for concrete are available in ABAQUS/Explicit, the Brittle Cracking Model and the Concrete Damaged Plasticity Model, and their suitability and limitations are well known. The aim of the present paper is to implement a damage-friction concrete constitutive model and to evaluate the performance of this model by comparing the predicted response with experimental data. The constitutive formulation of this material model is reviewed. In order to have consistent results, the parameter identification and calibration for the model have been performed. Several numerical simulations are presented in this paper, whose results allow for validating the capability of the proposed model for reproducing the typical nonlinear performances of concrete structures under different monotonic and cyclic load conditions. The results of the evaluation will be used for recommendations concerning the application and further improvements of the investigated model.

Keywords: Concrete, Numerical Simulation, constitutive model, ABAQUS

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17 Numerical Investigation for Ductile Fracture of an Aluminium Alloy 6061 T-6: Assessment of Critical J-Integral

Authors: R. Bensaada, R. Ferhoum, M. Almansba, M. Ould Ouali, N. E. Hannachi

Abstract:

The aim of this work is to simulate the ductile fracture of SEN specimens in aluminium alloy. The assessment of fracture toughness is performed with the calculation of Jc (the critical value of J-Integral) through the resistance curves. The study is done using finite element code calculation ABAQUSTM including an elastic plastic with damage model of material’s behaviour. The procedure involves specimens of four different thicknesses and four ligament sizes for every thickness. The material of study is an aluminium alloy 6061-T6 for which the necessary parameters to complete the study are given. We found the same results for the same specimen’s thickness and for different ligament sizes when the fracture criterion is evaluated.

Keywords: Damage, fracture toughness, J-integral, critical-j

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16 Comparative Study between Classical P-Q Method and Modern Fuzzy Controller Method to Improve the Power Quality of an Electrical Network

Authors: M. S. Boucherit, A. Morsli, N. Ould Cherchali, A. Tlemçani

Abstract:

This article presents two methods for the compensation of harmonics generated by a nonlinear load. The first is the classic method P-Q. The second is the controller by modern method of artificial intelligence specifically fuzzy logic. Both methods are applied to an Active Power Filter shunt (APFs) based on a three-phase voltage converter at five levels NPC topology. In calculating the harmonic currents of reference, we use the algorithm P-Q and pulse generation, we use the intersective PWM. For flexibility and dynamics, we use fuzzy logic. The results give us clear that the rate of Harmonic Distortion issued by fuzzy logic is better than P-Q.

Keywords: Fuzzy Logic Controller, total harmonic distortion (THD), P-Q method, pulse width modulation (PWM), shunt active power filter (sAPF)

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15 Elimination of Low Order Harmonics in Multilevel Inverter Using Nature-Inspired Metaheuristic Algorithm

Authors: M. S. Boucherit, A. Morsli, N. Ould Cherchali, A. Tlemçani

Abstract:

Nature-inspired metaheuristic algorithms, particularly those founded on swarm intelligence, have attracted much attention over the past decade. Firefly algorithm has appeared in approximately seven years ago, its literature has enlarged considerably with different applications. It is inspired by the behavior of fireflies. The aim of this paper is the application of firefly algorithm for solving a nonlinear algebraic system. This resolution is needed to study the Selective Harmonic Eliminated Pulse Width Modulation strategy (SHEPWM) to eliminate the low order harmonics; results have been applied on multilevel inverters. The final results from simulations indicate the elimination of the low order harmonics as desired. Finally, experimental results are presented to confirm the simulation results and validate the efficaciousness of the proposed approach.

Keywords: Multilevel Inverter, firefly algorithm, metaheuristic algorithm, SHEPWM

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14 Robust Diagnosability of PEMFC Based on Bond Graph LFT

Authors: Ould Bouamama, M. Bressel, D. Hissel, M. Hilairet

Abstract:

Fuel cell (FC) is one of the best alternatives of fossil energy. Recently, the research community of fuel cell has shown a considerable interest for diagnosis in view to ensure safety, security, and availability when faults occur in the process. The problematic for model based FC diagnosis consists in that the model is complex because of coupling of several kind of energies and the numerical values of parameters are not always known or are uncertain. The present paper deals with use of one tool: the Linear Fractional Transformation bond graph tool not only for uncertain modelling but also for monitorability (ability to detect and isolate faults) analysis and formal generation of robust fault indicators with respect to parameter uncertainties.The developed theory applied to a nonlinear FC system has proved its efficiency.

Keywords: Structural Analysis, Fuel Cell, fault detection and isolation (FDI), bond graph, robust diagnosis

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13 Isolation and Identification of the Dominant Flora of the Intestinal Microbiota of Rattus norvegicus an Algerian Firm West

Authors: B. Meddah, Karima Ould Yerou, A. Tir Touil

Abstract:

The intestinal flora also called the intestinal microbiota, consists of different bacteria and other microorganisms which occur naturally in the gastrointestinal tract organs components. These intestinal bacteria are present in their millions and help the functioning of the body in particular allowing aid to degradation of certain molecules into absorbable substrates. They also protect against invasion of the gut by other pathogenic bacteria, that is to say which may be responsible for disease. Factors like stress, antibiotics and diet can affect the balance of intestinal flora and in case of imbalance, digestive disorders type bloating, diarrhea or vomiting may occur. Rattus norvegicus of bad weight of 100 kg, an Algerian firm West are scarified and isolation of their ileum and colon respectively two Bactrian strains Escherichia coli and Lactobacillus are then purified and identified.

Keywords: Lactobacillus, Escherichia coli, Rattus norvegicus, intestinal flora, West Algerian farm

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12 Hybrid Approach for Controlling Inductive Load Fed by a Multicellular Converter by Using the Petri Nets

Authors: N. Ould Cherchali, A. Tlemçani, I. Bentchikou, F. Boudjema, D. Boukhetala

Abstract:

In this paper, hybrid approach is proposed to regulate the voltages of the floating capacitor multicell inverter and the current in the load. This structure makes it possible to ensure the distribution of the voltage stresses on the various low-voltage semiconductor components connected in series. And as the problem and to keep a constant voltage across the capacitors. Thus, it is necessary to ensure a distribution balanced voltages at the terminals of floating capacitors thanks to Algorithm develop for this, using the Petri nets. So we consider a three-cell converter represented as a hybrid system with eight modes of operation. The operating modes of the system are governed by the control reference voltage and a reference current. Finally, we present the results of the simulation with MATLAB/SIMULINK to illustrate the performances of this approach.

Keywords: Petri nets, Hybrid Control, floating condensers, multicellular converter

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11 Effects of the Type of Soil on the Efficiency of a Bioremediation Dispositive by Using Bacterium Hydrocarbonoclastes

Authors: Amel Bouderhem, Aminata Ould El Hadj Khelil, Amina N. Djrarbaoui, Aroussi Aroussi

Abstract:

The present work aims to find the influence of the nature of the soil on the effectiveness of the biodegradation of hydrocarbons by a mixture of bacterial strains hydrocarbonoclastes. Processes of bioaugmentation and biostimulation trial are applied to samples of soils polluted voluntarily by the crude oil. For the evaluation of the biodegradation of hydrocarbons, the bacterial load, the pH and organic carbon total are followed in the different experimental batches. He bacterial load of the sandy soil varies among the witnesses of 45,2 .108 CFU/ml at the beginning of the experimentation to 214,07.108 CFU/ml at the end of the experiment. Of the soil silty-clay varies between 103,31 .108 CFU/ml and 614,86.108 CFU/ml . It was found a strong increase in the bacterial biomass during the processing of all samples. This increase is more important in the samples of sand bioaugmente or biomass increased from 63.16 .108 CFU/ml to 309.68 .108 CFU/ml than in soil samples silty clay- bioaugmente whose content in bacteria evolved of 73,01 .108 CFU/ml to 631.80 . 108CFU/ml

Keywords: Bioremediation, Pollution, Hydrocarbons, Texture, ground, bacteria hydrocarbonoclastes

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10 Robust Diagnosis of an Electro-Mechanical Actuators, Bond Graph LFT Approach

Authors: A. Boulanoir, B. Ould Bouamama, A. Debiane, N. Achour

Abstract:

The paper deals with robust Fault Detection and isolation with respect to parameter uncertainties based on linear fractional transformation form (LFT) Bond graph. The innovative interest of the proposed methodology is the use only one representation for systematic generation of robust analytical redundancy relations and adaptive residual thresholds for sensibility analysis. Furthermore, the parameter uncertainties are introduced graphically in the bond graph model. The methodology applied to the nonlinear industrial Electro-Mechanical Actuators (EMA) used in avionic systems, has determined first the structural monitorability analysis (which component can be monitored) with given instrumentation architecture with any need of complex calculation and secondly robust fault indicators for online supervision.

Keywords: Mechatronic Systems, bond graph (BG), electro mechanical actuators (EMA), fault detection and isolation (FDI), linear fractional transformation (LFT), parameter uncertainties, avionic system

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9 A Formal Property Verification for Aspect-Oriented Programs in Software Development

Authors: Moustapha Bande, Hakima Ould-Slimane, Hanifa Boucheneb

Abstract:

Software development for complex systems requires efficient and automatic tools that can be used to verify the satisfiability of some critical properties such as security ones. With the emergence of Aspect-Oriented Programming (AOP), considerable work has been done in order to better modularize the separation of concerns in the software design and implementation. The goal is to prevent the cross-cutting concerns to be scattered across the multiple modules of the program and tangled with other modules. One of the key challenges in the aspect-oriented programs is to be sure that all the pieces put together at the weaving time ensure the satisfiability of the overall system requirements. Our paper focuses on this problem and proposes a formal property verification approach for a given property from the woven program. The approach is based on the control flow graph (CFG) of the woven program, and the use of a satisfiability modulo theories (SMT) solver to check whether each property (represented par one aspect) is satisfied or not once the weaving is done.

Keywords: Satisfiability modulo theories, Aspect-Oriented Programming, control flow graph, property verification

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8 Filler Elastomers Abrasion at Steady State: Optimal Use Conditions

Authors: Djeridi Rachid, Ould Ouali Mohand

Abstract:

The search of a mechanism for the elastomer abrasive wear study is an open issue. The practice difficulties are complex due to the complexity of deformation mechanism, to the complex mechanism of the material tearing and to the marked interactions between the tribological parameters. In this work, we present an experimental technique to study the elastomers abrasive wear. The interaction 'elastomer/indenter' implicate dependant ant temporary of different tribological parameters. Consequently, the phenomenon that governs this interaction is not easy to explain. An optimal elastomers compounding and an adequate utilization conditions of these materials that define its resistance at the abrasion is discussed. The results are confronted to theoretical models: the weight loss variation in function of blade angle or in function of cycle number is in agreement with rupture models and with the mechanism of fissures propagation during the material tearing in abrasive wear of filler elastomers. The weight loss in function of the sliding velocity shows the existence of a critical velocity that corresponds to the maximal wear. The adding of silica or black carbon influences in a different manner on wear abrasive behavior of filler elastomers.

Keywords: Tribology, abrasion wear, filler elastomer, hyperelastic

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7 Study of Two MPPTs for Photovoltaic Systems Using Controllers Based in Fuzzy Logic and Sliding Mode

Authors: M. S. Boucherit, L. Barazane, A. Morsli, N. Ould Cherchali

Abstract:

Photovoltaic power is widely used to supply isolated or unpopulated areas (lighting, pumping, etc.). Great advantage is that this source is inexhaustible, it offers great safety in use and it is clean. But the dynamic models used to describe a photovoltaic system are complicated and nonlinear and due to nonlinear I-V and P–V characteristics of photovoltaic generators, a maximum power point tracking technique (MPPT) is required to maximize the output power. In this paper, two online techniques of maximum power point tracking using robust controller for photovoltaic systems are proposed, the first technique use fuzzy logic controller (FLC) and the second use sliding mode controller (SMC) for photovoltaic systems. The two maximum power point tracking controllers receive the partial derivative of power as inputs, and the output is the duty cycle corresponding to maximum power. A Photovoltaic generator with Boost converter is developed using MATLAB/Simulink to verify the preferences of the proposed techniques. SMC technique provides a good tracking speed in fast changing irradiation and when the irradiation changes slowly or is constant the panel power of FLC technique presents a much smoother signal with less fluctuations.

Keywords: Fuzzy Logic Controller, Photovoltaic System, sliding mode controller, maximum power point, tracker

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6 Numerical Study of Natural Convection Heat Transfer in a Two-Dimensional Vertical Conical PartiallyAnnular Space

Authors: Belkacem Ould Said, Nourddine Retiel, Abdelilah Benazza, Mohamed Aichouni

Abstract:

In this paper, a numerical study of two-dimensional steady flow has been made of natural convection in a differentially heated vertical conical partially annular space. The heat transfer is assumed to take place by natural convection. The inner and outer surfaces of annulus are maintained at uniform wall temperature. The annulus is filled with air. The CFD FLUENT12.0 code is used to solve the governing equations of mass, momentum and energy using constant properties and the Boussinesq approximation for density variation. The streamlines and the isotherms of the fluid are presented for different annuli with different boundary conditions and Rayleigh numbers. Emphasis is placed on the influences of the height of the inner vertical cone on the flow and the temperature fields. In addition, the effects on the heat transfer are discussed for various values of physical parameters of the fluid and geometric parameters of the annulus. The heat transfer on the hot walls of the annulus is also calculated in order to make comparisons between the cylinder annulus for boundary conditions and several Rayleigh numbers. A good agreement of Nusselt number has been found between the present predictions and reference from the literature data.

Keywords: Heat Transfer, Numerical Simulation, natural convection, conical partially, annular space

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5 Evaluation of Moroccan Microalgae Spirulina platensis as a Potential Source of Natural Antioxidants

Authors: A. Amiri, T. Ould Bellahcen, I. Touam, F. Hmimid, A. El Amrani, M. Cherki

Abstract:

The antioxidant activity of three extracts (water, lipidic and ethanolic) prepared from the microalgae Spirulina platensis isolated from Moroccan lake, using 2, 2 diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis ethylbenzthiazoline-6-sulfonic acid (ABTS) radical assay, was studied and compared. The obtained results revealed that the IC₅₀ found using DPPH were lower than that of ABTS for all extracts from these planktonic blue-green algae. The high levels of phenolic and flavonoid content were found in the ethanolic extract 0,33 ± 0,01 mg GAE/g dw and 0,21 ± 0,01 mg quercetin/g dw respectively. In addition, using DPPH, the highest activity with IC₅₀ = 0,449 ± 0,083 mg/ml, was found for the ethanolic extract, followed by that of lipidic extract (IC₅₀ = 0,491 ± 0,059 mg/ml). The lowest activity was for the aqueous extract (IC₅₀ = 4,148 ± 0,132 mg/ml). For ABTS, the highest activity was observed for the lipidic extract with IC₅₀ = 0,740 ± 0,012 mg/ml, while, the aqueous extract recorded the lowest activity (IC₅₀ = 6,914 ± 0, 0067 mg/ml). A moderate activity was showed for the ethanolic extract (IC₅₀ = 5,852 ± 0, 0171 mg/ml). It can be concluded from this first study that Spirulina platensis extracts show an interesting antioxidant and antiradicals properties suggesting that this alga could be used as a potential source of antioxidants. A qualitative and quantitative analysis of polyphenol and flavonoids in the extracts using HPLC is in progress so as to study the correlation between the antioxidant activity and chemical composition.

Keywords: DPPH, antioxidant, ABTS, Spirulina platensis

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4 Structural and Optical Properties of RF-Sputtered ZnS and Zn(S,O) Thin Films

Authors: Abdelkader Outzourhit, Ould Mohamed Cheikh, Mounir Chaik, Hind El Aakib, Mohamed Aggour

Abstract:

Zinc sulfide [ZnS] and oxygenated zinc sulfide Zn(O,S) thin films were deposited on glass substrates, by reactive cathodic radio-frequency (RF) sputtering. The substrates power and percentage of oxygen were varied in the range of 100W to 250W and from 5% to 20% respectively. The structural, morphological and optical properties of these thin films were investigated. The optical properties (mainly the refractive index, absorption coefficient and optical band gap) were examined by optical transmission measurements in the ultraviolet-visible-near Infrared wavelength range. XRD analysis indicated that all sputtered ZnS films were a single phase with a preferential orientation along the (111) plane of zinc blend (ZB). The crystallite size was in the range of 19.5 nm to 48.5 nm, the crystallite size varied with RF power reaching a maximum at 200 W. The Zn(O,S) films, on the other hand, were amorphous. UV-Visible, measurements showed that the ZnS film had more than 80% transmittance in the visible wavelength region while that of Zn(O,S is 85%. Moreover, it was observed that the band gap energy of the ZnS films increases slightly from 3.4 to 3.52 eV as the RF power was increased. The optical band gap of Zn(O,S), on the other hand, decreased from 4.2 to 3.89 eV as the oxygen partial pressure is increased in the sputtering atmosphere at a fixed RF-power. Scanning electron microscopy observations revealed smooth surfaces for both type of films. The X-ray reflectometry measurements on the ZnS films showed that the density of the films (3.9 g/cm3) is close that of bulk ZnS.

Keywords: thin films Zn(O, S) properties, Zn(O, S) by Rf-sputtering, ZnS for solar cells, thin films for renewable energy

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3 Assessment of Hemostatic Activity of the Aqueous Extract of Leaves of Marrubium vulgare L.: A Mediterranean Lamiaceae Algeria

Authors: Nabil Ghedadba, Abdessemed Samira, Leila Hambaba, Sidi Mohamed Ould Mokhtar, Nassima Fercha, Houas Bousselsela

Abstract:

The overall objective of this study was to evaluate in vitro the hemostatic activity of secondary metabolites (polyphenols, flavonoids, and tannins) of Marrubium vulgare leaves, aromatic plant widely used in traditional medicine for the treatment of asthma, cough, diabetes (by its effect on the pancreas to secrete insulin), heart disease, fever has a high efficiency as against inflammation. Qualitative analysis of the aqueous extract (AQE) by thin layer chromatography revealed the presence of quercetin, kaempferol and rutin. Quantification of total phenols by Folin Ciocalteu method and flavonoids by AlCl3 method gave high values with AQE: 175±0.80 mg GAE per 100g of the dry matter, 23.86±0.36 mg QE per 100g of dry matter. Moreover, the assay of condensed tannins by the vanillin method showed that AQE contains the highest value: 16.55±0.03 mg e-catechin per 100 g of dry matter. Assessment of hemostatic activity by the plasma recalcification method (time of Howell) has allowed us to discover the surprising dose dependent anticoagulant effect of AQE lyophilized from leaves of M. vulgare. A positive linear correlation between the two parameters studied: the content of condensed tannins and hemostatic activity (r=0.96) were used to highlight a possible role of these compounds that are potent vasoconstrictor activity in hemostatic. From these results we can see that Marrubium vulgre could be used for the treatment of health.

Keywords: Marrubium vulgare L, aqueous extract, phenolic compounds dosing, hemostatic activity, condensed tannins

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2 Chemical Characterization and Prebiotic Effect of Water-Soluble Polysaccharides from Zizyphus lotus Leaves

Authors: Zakaria Boual, Abdellah Kemassi, Toufik Chouana, Philippe Michaud, Mohammed Didi Ould El Hadj

Abstract:

In order to investigate the prebiotic potential of oligosaccharides prepared by chemical hydrolysis of water-soluble polysaccharides (WSP) from Zizyphus lotus leaves, the effect of oligosaccharides on bacterial growth was studied. The chemical composition of WSP was evaluated by colorimetric assays revealed the average values: 7.05±0.73% proteins and 86.21±0.74% carbohydrates, among them 64.81±0.42% are neutral sugar and the rest 16.25±1.62% are uronic acids. The characterization of monosaccharides was determined by high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) was found to be composed of galactose (23.95%), glucose (21.30%), rhamnose (20.28%), arabinose (9.55%), and glucuronic acid (22.95%). The effects of oligosaccharides on the growth of lactic acid bacteria were compared with those of fructo-oligosaccharide (RP95). The oligosaccharides concentration was 1g/L of man rogosa sharpe broth. Bacterial growth was assessed during 2, 4.5, 6.5, 9, 12, 16 and 24 h by measuring the optical density of the cultures at 600 nm (OD600) and pH values. During fermentation, pH in broth cultures decreased from 6.7 to 5.87±0.15. The enumeration of lactic acid bacteria indicated that oligosaccharides led to a significant increase in bacteria (P≤0.05) compared to the control. The fermentative metabolism appeared to be faster on RP95 than on oligosaccharides from Zizyphus lotus leaves. Both RP95 and oligosaccharides showed clear prebiotic effects, but had differences in fermentation kinetics because of to the different degree of polymerization. This study shows the prebiotic effectiveness of oligosaccharides, and provides proof for the selection of leaves of Zizyphus lotus for use as functional food ingredients.

Keywords: Characterization, Polysaccharides, Zizyphus lotus, prebiotic effects

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1 Study of the Influence of the Region, the Depth and the Drying Process on the Chemical Composition of Gelidium sesquipedale

Authors: A. Amiri, T. Ould Bellahcen, F. Hmimid, M. Cherki, I. Taouam

Abstract:

The Moroccan coasts represent an important wealth of red algae which have an economic interest. Among these algae, the Gelidium sesquipedale, which is exploited industrially for its richness in agar. The aim of this study is to establish a general overview of the macronutrient composition of Gelidium sesquipedale and to compare this composition according to three factors: the harvest site (El Jadida, Casablanca and Mohammadia), the harvest depth (coast and depth) and the drying process (open air and oven). Proteins, lipids, and carbohydrates are measured by different methods. The analysis of results show that the protein concentrations of the El Jadida and Mohammadia samples are significantly higher than that of Casablanca (0.026 ± 0.0007 µg/µg DW 0.024 ± 0.001 µg/µg DW and 0.006 ± 0.0007 µg/µg DW, p < 0.05 respectively). However, Casablanca samples are significantly richer in total sugars (0.023 ± 0.002 µg/µg DW, p < 0.05) and less rich in reducing sugars (0.0001 ± 0.00001 µg/µg DW, p < 0.05) compared to other samples. The lipid concentrations of the samples from the three harvest sites do not show any significant difference. With respect to depth, only total protein and total sugar concentrations were significantly higher in the coast versus depth samples (0.035 ± 0.004 µg/µg DW vs. 0.026 ± 0.0007 µg/µg DW and 0.035 ± 0.006 µg/µg DW vs. 0.012 ± 0.005 µg/µg DW p < 0.05 respectively). For the drying process, protein, total sugars and lipid concentrations were significantly higher in open air samples compared to oven samples (0.006 ± 0.0007 µg/µg DW). vs 0.004 ± 0.0003 µg/µg DW, 0.023 ± 0.002 µg/µg DW vs 0.007 ± 0.002 µg/µg DW and 8% vs 4% p < 0.05 respectively). Our results demonstrate that the chemical composition of Gelidium sesquipedale varies according to the harvest region. In addition, samples harvested on the coast and dried in the open air are the richest in macronutrients.

Keywords: Drying, region, biochemical composition, depth, red algae, Gelidium sesquipedale

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